Disabled vet needing new engine

I am a Gulf War veteran who has been sick ever since I returned, mainly with a constant headache which gets to be a migraine or cluster headache often, but for most of that time, I have been able to make a life for myself. Buy the last eight years, my health has gotten much worse, and I have not been able to hold down a job. The VA has continually denied my disability claims, until 2015, when they finally gave me 10℅ for my back and 0℅ for my headaches... But they promptly started taking the 10℅ and charging me for all of my meds that are not related to my disabilities... But, I did get Social Security disability, so I am on a very limited income.  I rely on my vehicle for transportation to my medical appointments, which I haven't been able to go to since the engine failed, also to pick my youngest son up from school, and of course all of the various other tasks that need to be performed, such as going to the store, etc... I cannot afford to buy another vehicle, so my only option is to repair the one I have, but I don't have the money to fix it either. The various veterans organizations don't have the resources to help to this extent, so I am asking for the kindness of the people here. Any help will be greatly appreciated.